Why do messages from Message Service go directly through gRPC instead of Kafka?

Messages from Message Service are sent directly via gRPC, not through Kafka, because:

• Low latency and synchronicity. gRPC provides fast bidirectional data exchange with low latency, which is important for real-time services.
• Direct interaction. For some scenarios, an instant response or delivery confirmation is needed, which is difficult to implement through an asynchronous queue.
• Simplicity and reliability. gRPC uses HTTP/2, supports streaming, and efficient serialization (Protocol Buffers).
• Kafka is suitable for asynchronous processing and high throughput, but not for synchronous requests expecting a response.

Thus, the choice of gRPC is driven by requirements for speed, reliability, and the nature of communication between services in Message Service.